Download Epicardial cyst- a case report

Downloaded from http://thorax.bmj.com/ on May 6, 2017 - Published by group.bmj.com
Thorax (1972), 27, 503.
Epicardial cyst-
a case
report
M. H. EDWARDS and A. AHMAD
The Brompton Hospital, London
The first successful removal of an epicardial cyst is reported. Evidence is presented to demonstrate that the cyst developed as a result of an abnormality occurring within the first five weeks
of fetal life.
Pericardial cysts are well recognized, comprising
7 % of all mediastinal tumours (Nelson, Shefts, and
Bowers, 1957). Unilocular, thin-walled sacs, they
lie usually in the anterior costophrenic angle in
close association with the pericardium. They contain clear fluid and occasionally communicate with
the pericardial cavity.
In contrast, a similar cyst arising inside the
pericardial cavity, and attached to the heart, is
exceedingly rare. Only three reports showing any
resemblance to the case described below have been
found in the literature. Gould (1960) described an
intrapericardial cyst in a stillborn child, as well
as a small multilocular cyst arising from the ventricle of an adult also found at necropsy. Piwnica
and Menage (1962) described the successful removal of a large cyst arising from between the
aorta and the pulmonary artery in a child. Preoperative irradiation had destroyed the cyst lining,
but the site of the cyst suggests that it was bronchogenic rather than pericardial in origin.
Although the cyst described below may be
unique, it has relevance to the aetiology of pericardial cysts in general.
CASE EPORT
R.D., a 43-year-old electrical engineer, was admitted
to hospital in February 1969 for investigation. For
the previous two years he had noticed slight breathlessness on climbing stairs and an enlarged cardiac
silhouette had been reported on mass miniature radiography. He had been treated for rheumatic fever at
the age of 7 years. He smoked 20 cigarettes a day
until 1964 and consumed moderate quantities of
alcohol.
Examination revealed a healthy, heavily built man;
there were no abnormal physical signs except an
increased jugular 'a' wave and reversed splitting of
the second heart sound in the pulmonary area. The
pulse rate was regular at 80 beats per minute and the
blood pressure was 110/70 mmHg.
Routine investigations showed no haematological or
biochemical abnormality, and in particular the white
cell count, blood urea, protein-bound iodine and serum
cholesterol levels were within normal limits.
Chest radiographs confirmed the presence of
moderate cardiac enlargement without abnormality of
the pulmonary vasculature (Figs. 1 and 2).
Right and left heart catheterization demonstrated
normal haemodynamics apart from raised end-diastolic
pressures in the right ventricle (6-9 mmHg) and in the
left ventricle (10-15 mmHg).
Cineangiography was performed by injection of
contrast medium into the right atrium, showing that
all the heart chambers were displaced to the right by
a large mass situated on the left lateral aspect of the
heart (Fig. 3). The mass was very unyielding to left
ventricular movement.
OPERATION A left anterolateral thoracotomy was performed through the fifth intercostal space. The pericardium was healthy and was opened in front of the
phrenic nerve. The pericardial cavity contained a
little clear fluid and a large, tense, unilocular, thinwalled cyst displacing the heart to the right.
After removing approximately 500 ml of clear
straw-coloured fluid from the cyst, its attachment to
the heart near the coronary sinus, well clear of the
pulmonary veins and the oblique vein of Marshall,
was visible; the cyst wall was excised completely,
except for a small area at its base which was fused
with the visceral pericardium. The parietal pericardium
was left partly open and the thoracotomy wound was
closed after draining the left pleural cavity.
The patient made a satisfactory recovery apart
from the development of a pericardial effusion. One
month after operation the pericardial cavity was
drained of 2 litres of old blood through a subcostal
incision. Subsequenly- the patient continued to improve and is now fit and well.
A radiograph taken three months after thoracotomy
showed diminution of the size of the heart shadow
(Fig. 4).
Histological examination f' the cyst demonstrated
a fibrous wall lined by a layer of flattened cells.
503
Downloaded from http://thorax.bmj.com/ on May 6, 2017 - Published by group.bmj.com
504
M. H. Edwards and A. Ahmad
FIG. 1
FIGS. 1 and 2. Moderate enlargement of the cardiac outline.
FIG. 2
FIG. 3. Cineangiography shows that all the chambers are
displaced to the right by a mass situated on the left lateral
aspect of the heart.
Downloaded from http://thorax.bmj.com/ on May 6, 2017 - Published by group.bmj.com
Epicardial cyst-a case report
505
FIG. 4. Radiography three months after excision of the cyst shows a diminution of the size of the heart shadow.
DISCUSSION
Cystic lesions arising in the mediastinum have been
extensively reviewed (Davis, Dorsey, and Scanlon,
1953; De Roover, Maisin, and Lacquet, 1963).
Those found inside the pericardium, on the other
hand, are less well known but have been described
by Loehr (1952) in an excellent survey of cyst-like
shadows inseparable radiologically from the heart
and pericardium. Chronic pericarditis or tuberculosis may be preceded by bouts of illness;
tuberculous foci are seen in the lungs and calcification in the pericardium is usually visualized on
radiographs. The pericardium is chronically
inflamed and tubercle bacilli may be isolated.
Loehr stresses that hydatid disease of the pericardium is nearly always secondary to rupture of
a cyst in the myocardium, and that the calcified
walls of these myocardial cysts can be seen radiographically. Perlstein (1918) reported that malignant tumours of the heart and pericardium,
whether primary or secondary, usually progress
rapidly and show evidence of metastasis clinically
and radiogically at an early stage, but added that
pericardial effusions and cystic degenerations were
common.
Benign cysts inside the pericardial cavity show
the same structures as those outside. On rare
occasions a teratomatous cyst can be diagnosed
radiographically by the presence of teeth. At operation, hair in the cyst is diagnostic. Usually a teratoma is indistinguishable from a bronchogenic cyst
until the presence of tissue from all three germ
layers is seen on microscopic examination of the
former. The wall of both types is usually calcified,
and the fluid contents are viscid, varying in colour
from yellow to muddy brown. However, Dabbs,
Berg, and Peirce (1957) suggested that branchogenic cysts were usually attached to the region of
the great vessels, whereas teratomas were more
likely to be found at the side of the heart itself.
There has been no convincing report of intrapericardial lymphangiomatous cysts, but, when
found outside the pericardial cavity, they are
usually multiple, of various sizes, fused with
mediastinal tissue, and contain crystal-clear fluid.
The lining of the cyst wall consists of a layer of
flattened endothelial cells, identical with that of a
pericardial cyst, so that the distinction between the
two depends on the macroscopic appearances.
It was, therefore, concluded that the cyst
described above was derived from pericardial
Downloaded from http://thorax.bmj.com/ on May 6, 2017 - Published by group.bmj.com
506
M. H. Edwards and A. A hmad
tissue and should be called an epicardial cyst.
EMBRYOLOGY Within five weeks of fertilization,
small spaces in the mesoderm have coalesced
around the heart tube to form the pericardial
cavity. Lambert (1940) considers that extrapericardial cysts develop as a result of failure of
coalescence of these mesodermal spaces. Lillie,
McDonald, and Clagett (1950), however, suggest
that these malformations occur at a later date
when the coalescence is complete; at this stage
the pericardial cavity communicates with the peritoneum by means of the paired pleuroperitoneal
canals running dorsally, and also possesses two
ventral recesses which end in the septum transversum. Abnormalities of development of the
ventral recesses, Lillie et al. claim, would explain
not only the presence of extrapericardial cysts,
but also pericardial diverticula.
However, even later, as the pleural cavities
enlarge to accommodate the developing lungs,
folds appear in the pleural lining and may be cut
off to produce extrapericardial cysts. Kindred, in
a personal communication to Drash and Hyer
(1950), demonstrated a section of a 30 mm human
fetus with this infolding clearly shown.
A satisfactory explanation of the development
of a pericardial cyst from the visceral pericardium
is afforded by Lambert's theory of failed coalescence of pericardial lacunae.
It is improbable that pleural infolding or
abnormal development of a ventral pericardial
recess would produce such a cyst, since the visceral
pericardium is fully developed before these events
occur. It would seem that Lambert's theory is
acceptable for the aetiology of pericardial cysts
both inside and outside the pericardial cavity.
We express our thanks to Mr. S. C. Lennox, Dr. J. N.
Mickerson, and Dr. R. Gibson for permission to
publish details of their case; to Dr. K. F. Hinson for
the histology; to Mr. P. A. Cullum, King's College
Hospital, for advice and encouragement; and to Mr.
K. G. Morman, Chester Beatty Research Institute, for
the photographs.
REFERENCES
Dabbs, C. H., Berg, R., and Peirce, E. C. (1957). Intrapericardial bronchogenic cysts. J. thorac. Surg., 34, 718.
Davis, C., Dorsey, J., and Scanlon, E. (1953). Cysts about
the pericardium. Arch. Surg., 67, 110.
De Roover, Ph., Maisin, J., and Lacquet, A. (1963). Congenital pleuro-pericardial cysts. Thorax, 18, 146.
Drash, E. C., and Hyer, H. J. (1950). Mesothelial mediastinal
cysts. J. thorac. Surg., 19, 755.
Gould, S. E. (1960). Pathology of the Heart. Thomas, Springfield, Illinois.
Lambert, A. V. S. (1940). Etiology of thin-walled thoracic
cysts. J. thorac. Surg., 10, 1.
Lillie, W. I., McDonald, J. R., and Clagett, 0. T. (1950).
Pericardial celomic cysts and pericardial diverticula.
J. thorac. Surg., 20, 494.
Loehr, W. M. (1952). Pericardial cysts. Amer. J. Roentgenol.,
68, 584.
Nelson, T. G., Shefts, L. M., and Bowers, W. F. (1957).
Mediastinal tumours; an analysis of 141 cases. Dis.
Chest, 32, 123.
Perlstein, I. (1918). Sarcoma of the heart. Amer. J. med. Sci.,
156, 214.
Piwnica, A., and Menage, C. (1962). Les tumeurs kystiques
intra-pericardiques. J. Chir. (Paris), 84, 543.
Downloaded from http://thorax.bmj.com/ on May 6, 2017 - Published by group.bmj.com
Epicardial cyst−−a case report
M. H. Edwards and A. Ahmad
Thorax 1972 27: 503-506
doi: 10.1136/thx.27.4.503
Updated information and services can be found at:
http://thorax.bmj.com/content/27/4/503
These include:
Email alerting
service
Receive free email alerts when new articles cite this
article. Sign up in the box at the top right corner of
the online article.
Notes
To request permissions go to:
http://group.bmj.com/group/rights-licensing/permissions
To order reprints go to:
http://journals.bmj.com/cgi/reprintform
To subscribe to BMJ go to:
http://group.bmj.com/subscribe/